Bimonthly

ISSN 1006-9585

CN 11-3693/P

+Advanced Search 中文版
    • Current Issue
    • |
    • Online First
    • |
    • Special Articles
    • |
    • Most Read
    • |
    • Archive
      Select All
      Display Method: |

      Volume 26,2021 Issue 5

      Select All
      Display Method: |

      Online First

      • SONG Zongpeng, LIU Xiaolin, FENG Shuanglei, WANG Bo, JIN Shuanglong, GUO Yuyang

        Available online:October 12, 2021  DOI: 10.3878/j.issn.1006-9585.2021.21048

        Abstract:The spatio-temporal distribution information of freezing rain has high practical value for the electric power, transportation, communications, agriculture and forestry sectors. Previous research was mostly based on observational data, limited by the short length of the data, uneven distribution and partial lack, there may be insufficient understanding. The new-generation ERA5 reanalysis data contains freezing rain data not provided by other reanalysis data, which provides the possibility to further understand the spatio-temporal distribution in China. This paper uses ERA5 freezing rain data to analyze the annual average and interdecadal characteristics of China’s annual freezing rain days and annual freezing rainfall from 1979 to 2020. The spatio-temporal distribution characteristics of the EOF modes are also studied. The results show that China’s annual average freezing rain days and annual average freezing rainfall are most concentrated in Guizhou, Hunan, et al., directly affecting 7 ‘West-to-East’ ultra-high voltage (UHV) direct-current (DC) transmission lines, with a total length of about 4900 kilometers; The number of annual freezing rain days and annual freezing rainfall in concentrated areas are decreasing; As for EOF mode 1 (variance contribution 36.96%) of the number of freezing rain days, it is mainly distributed to the east of the Heihe-Tengchong line, and the overall trend is decreasing, and with the Qinling-Huaihe line as the boundary, there is a north-south reverse distribution; EOF mode 2 (variance contribution 11.56%) of the number of freezing rain days reflects two anti-phase regions in the southern freezing rain concentrated area, and the phase alternate period is 2 to 4 years; The EOF mode distribution of the annual freezing rainfall are similar to the annual number of freezing rain days.

      • WANG Zhuofan, HAN Zhe, LI Shuanglin, LI Guoping, SUN Xueqian

        Available online:October 12, 2021  DOI: 10.3878/j.issn.1006-9585.2021.21062

        Abstract:Based on the sea ice data from 1979 to 2017, this work used linear regression and a linear baroclinic model to investigate the differences of Antarctic sea ice during two types of El Ni?o events (EP and CP) and its possible physical mechanisms. The results suggest that the amplitude and the spatial pattern of sea ice anomalies are different, although there are some similarities. The sea ice anomalies in the Ross Sea and Amundsen Sea in EP and CP event are negative, but they are stronger in the EP event than CP event. The sea ice anomalies in the Weddell Sea are positive, and they are stronger and northwestward in the EP event relative to the CP event. The difference of sea temperature anomalies intensity between EP and CP events is an important reason for the different amplitude of sea ice. The sea surface temperature anomalies are stronger in the EP event than the CP event, and force a Pacific-South America teleconnection pattern with a stronger high-pressure anomaly. Such atmospheric circulation leads to northeast wind anomaly in Ross Sea in the EP event, which transport sea ice to high latitudes and the sea ice decreases, and causes south wind anomaly in Weddell Sea, which accumulate sea ice on the northern Weddell Sea. Compared to the EP event, the Pacific-South America teleconnection anomaly forced by the CP event is weaker, which induced weaker sea ice anomalies. In fact, the positive anomaly of sea ice in Weddell Sea has appeared in previous November during the CP event, and strengthened due to the ice-albedo feedback in the following spring. Our results suggest that sea ice anomalies are stronger when the sea surface temperature anomalies in the tropical Pacific are stronger. It is different from that indicated in previous studies, but is more reasonable.

      • YANG Yang, LIN Zhaohui, LUO Lifeng

        Available online:October 11, 2021  DOI: 10.3878/j.issn.1006-9585.2021.21060

        Abstract:Given the important role of land-atmosphere interaction in extreme hot events, the multi-timescale characteristics of the coupling strength between surface air temperature and soil moisture, as well as soil temperature during summer in China has been analyzed using the ERA5-Land reanalysis dataset. Results show that the aforementioned four indices of land-atmosphere coupling strength (LACs) vary with regions. Specifically, “hot spots”, where variation in land surface has remarkable effect on surface air temperature through the latent heat flux, are mainly found in Northwest China and the Yangtze River basin; Nevertheless, in terms of LAC defined by the sensitivity of surface air temperature to land condition anomalies through the sensible heat exchange, the “hot spots” are mainly located in Hetao-Inner Mongolia areas, southwestern Xinjiang, and part of south Yangtze River. This indicates that the differences between the spatial distributions of four LACs could be largely explained by the dominant processes responsible for impact of land conditions on surface air temperature anomalies. It’s also found that the LAC varies a lot with timescales, with the coupling strength in monthly timescale significantly weaker than that of shorter timescales (i.e., daily-pentad-ten day); Besides, the land surface-latent heat flux-air temperature coupling strength gets weaker in majority parts of China with the timescale increasing from one day to ten days, while the land surface-sensible heat flux-air temperature coupling strength gets stronger over the northern parts of China with increasing timescales, and still gets weaker in other regions. Furthermore, subsurface soil moisture-related LAC is found to be weaker compared with that of surface one in Northwest China, but changes in subsurface soil-air temperature coupling strength of other metrics are small compared with that in surface layer.

      Select All
      Display Method: |
      • WANG Zhe, WANG Zifa, LI Jie, ZHENG Haitao, YAN Pingzhong, LI Jianjun

        2014,19(2):153-163, DOI: 10.3878/j.issn.1006-9585.2014.13231

        Abstract:An aerosol-optical module based on Mie scattering theory has been implemented in the Nested Air Quality Prediction Modeling System (NAQPMS), and a new coupler has been developed to deal with the interaction between the mesoscale meteorology model WRF (Weather Research and Forecasting Model) and NAQPMS. The one-way off-line and two-way coupled WRF-NAQPMS models are compared to simulate the severe haze in the Beijing-Tianjin-Hebei area from 27 September to 1 October 2013. The results show that the simulated meteorological elements and PM2.5 concentrations from the two-way coupled model with the aerosol direct radiation effect are more consistent with observations. During the haze period, the boundary layer meteorological elements change significantly because of the aerosol direct radiation effect over the Beijing-Tianjin-Hebei area: Incoming solar radiation is reduced by 25%, the 2-m temperature decreases by 1 ℃, the turbulent kinetic energy is reduced by 25%, the 10-m wind speed decreases by up to 0.2 m/s, and the planetary boundary layer (PBL) height is reduced by 25%. These changes make the atmospheric boundary layer more stable and further exacerbate air pollution over the areas where it is already severe, for example, the PM2.5 concentration increases by up to 30% over Shijiazhuang City. The analysis indicates that there is a positive feedback mechanism between haze and boundary layer meteorology, and the two-way coupled model incorporating this feedback is helpful for accurate simulation and forecasting of haze pollution processes.

      • ZHENG Si Yi, LIU Shu Hua

        2008,13(2):123-134, DOI: 10.3878/j.issn.1006-9585.2008.02.02

        Abstract:利用1961~2000年北京13个台站的气候观测资料及北京统计年鉴资料,分析了过去40年北京城区、郊区的气温、相对湿度和降水等气候因子的年际、季节变化趋势,结合北京城市化进程中人口、基本设施投资额、房屋施工面积和道路面积等城市发展数据的年际变化进行分析。结果表明:在这40年中,北京城区、郊区的年平均温度都呈明显上升趋势,城区比郊区上升幅度快,热岛强度也在不断加强,其中以城区最低温度上升最为明显,并且热岛强度与北京人口等城市发展数据的年际变化有较强的相关性。城区年平均相对湿度总体呈下降趋势,郊区则略有上升;本地年均降水量呈下降趋势,城区下降幅度比郊区明显,并且波动性增强。各气候因子的季节变化趋势总体上与年平均变化趋势一致,个别季节变化趋势受城市化及季节自身因素影响,与年平均变化趋势有所差异。过去40年北京城区、郊区的气候演变趋势及与城市发展数据的关系表明,城市的快速发展和城市化进程的加快已经对北京局地气候变化产生了重要的影响。

      • Ren Guoyu, Feng Guolin, Yan Zhongwei

        2010,15(4):337-353, DOI: 10.3878/j.issn.1006-9585.2010.04.01

        Abstract:国家“十一五”科技支撑计划重点项目“我国主要极端气候事件及重大气象灾害监测、检测和预测”对相关科学问题研究工作做了部署,其中课题二“近百年来我国极端天气气候事件变化特征及其影响(2007BAC29B02)”重点探讨全球变暖背景下中国区域极端气候变化规律。经过近两年多时间的研究,课题组取得了若干可喜的成果。

      • Zhao Tianbao, Ailikun, Feng Jingming

        2004,9(2):278-294, DOI: 10.3878/j.issn.1006-9585.2004.02.05

        Abstract:美国国家环境预报中心(NCEP)和国家大气中心(NCAR)的全球再分析资料,在很多气候模拟和预测研究中都被作为区域气候模式的驱动场和初始场资料,并用来检验模拟结果的.作者通过对NCEP的2种再分析资料NCEPI和NCEPⅡ与中国台站观测资料的月平均温度和月降水总量进行相互插值,分析和比较了NCEPⅠ、NCEPⅡ再分析值与中国区域内观测值之间的差异以及2种再分析资料之间的差异.从结果可以看到,NCEP再分析资料的月平均温度较观测值普遍偏低,而月降水总量较观测值则偏高;就季节变化而言,NCEP再分析值在夏季和年平均模拟的较好,冬季较差.同时可以看到,在温度和降水方面NCEPⅡ较NCEPⅠ都有所改进,尤其在中国东部地区,改进较为明显.

      • Xia Junrong, Wang Pucai, Min Min

        2011,16(6):733-741, DOI: 10.3878/j.issn.1006-9585.2011.06.07

        Abstract:A field performance of Doppler wind lidar Windcube (released by Leosphere Company) was conducted by Institute of Atmospheric Physics, Chinese Academy of Sciences (IAP/CAS) and Leosphere Company (from France) at the 325 m meteorological tower site (a part of IAP, located between 3rd North Ring Road and 4th North Ring Road) from 11 December to 14 December 2007. The intercomparison of wind speed and wind direction obtained by Windcube and wind cup anemometers (fixed in the meteorological tower) shows that:1) 10 min averaged wind speed is highly consistent between two types of wind data at six matched levels (63 m, 80 m, 100 m, 120 m, 160 m, and 200 m), the correlation coefficients all equal or exceed 0.98. 2) 10 min averaged wind direction is calculated with the vector method, the correlation coefficients of averaged wind direction at the six levels are 0.99. 3) In comparison with domestic Doppler wind lidar, Windcube performs slightly better in wind speed measuring, and equally well in wind direction measuring. The intercomparison indicates that Windcube is a reliable and swift mobile system mea suring wind profile at low levels.

      • JI Dongsheng, WANG Yuesi, SUN Yang, MA Zhiqiang

        2009,14(1):69-76, DOI: 10.3878/j.issn.1006-9585.2009.01.08

        Abstract:作为酸雨和细粒子的前体物,SO2对空气质量和人体健康乃至气候与环境的影响十分重要,特别是在不利于扩散的气象条件下,SO2可造成城市短时间严重污染事件。作者以2006年北京325 m气象塔15 m观测平台SO2观测数据为基础,结合同步气象资料分析研究发现:1) SO2浓度冬季高、夏季低;全年日均值为(22.5±22.1)×10-9,最大日均值能达到113×10-9。日变化呈现双峰型,峰值出现在北京时间08:00和22:00;并且季节差异明显,冬季浓度为夏季的4.5倍,采暖期为非采暖期的3.2倍。2) 风向、风速与SO2扩散和输送密切相关,高浓度SO2在东北、东、西方向上出现频率分别为25.8%、13.8%和11.8%;而西北、北方向上的风速越大对SO2清除效果越好。3)利用平均晴空指数划分采暖期阴霾天和晴天,发现阴霾天混合层高度与平均风速仅为(376±204) m和1.1 m·s-1,容易造成SO2累积。4) SO2污染过程呈现周期性的局地累积—清除特征,地形、静风和暖低压是造成北京2006年1月一次重污染事件的成因。

      • Liu Yuzhi

        1999,4(1):98-103, DOI: 10.3878/j.issn.1006-9585.1999.01.21

        Abstract:将1951~1980年郑州地区的气象要素(气温、风速、降雨量)的距平值与“五运六气”学说所推论气象作对比分析,两者结果比较一致。继之,收集了1953~1983年同一地区传染性肝炎、痢疾、伤寒、流行性感冒、猩红热、流行性乙型脑炎(这6种病在1983年以前均无疫苗或无有效预防)的流行资料进行分析,说明“五运六气”学说中的发病率与气候变化有较好的关系。

      • CAI Rongshuo, CHEN Jilong, TAN Hongjian

        2011,16(1):94-104, DOI: 10.3878/j.issn.1006-9585.2011.01.09

        Abstract:Based on the long time series of mean Sea Surface Temperature (SST) and high-resolution wind field reanalysis data such as HadISST and ERA-40 reanalysis data, the variations of the SST in the offshore area of China and their relationship with the East Asian Monsoon (EAM) in winter (December to the next February) and summer (June to August) are analyzed using the Empirical Orthogonal Function (EOF) and linear regression analysis methods. The results show that: 1) The SST in the offshore area of China in winter or summer exhibited significant interannual and interdecadal variations, and experienced a climate shift in the mid-1980s. The areas with the strongest increase in SST are located in the East China Sea (ECS) in winter and in the Yellow Sea in summer. The SST increased by 1.96°C in winter for the period of 1955-2005 and 1.10 °C in summer for the period of 1971-2006. 2)The EAM has displayed distinct interannual and interdecadal variations with a weakening trend since the end of the 1980s in winter, and since the end of the 1970s in summer. In addition, the linear regression analysis indicates the relationship of the SST to EAM in winter on interdecadal timescale is closer than that on interannual timescale. The interdecadal weakening trend of EAM in winter contributes to the rise in SST in the offshore areas of China, particularly significant in the ECS. Moreover, the related areas of winter or summer mean SST on the interannual timescale in the offshore area of China to the EAM are located in the South China Sea (SCS), and the relationship in winter is much more obvious than that in summer. It is found that the interannual variation of SST in the SCS has obvious relation to the anomalies of the meridional southward and northward winds over the SCS and zonal migration of the subtropical anticyclone over the western Pacific.

      • ZHAO Tian-Bao, FU Cong-Bin

        2006,11(1):14-32, DOI: 10.3878/j.issn.1006-9585.2006.01.02

        Abstract:再分析资料在气候变化研究中有着广泛的应用,但是再分析资料在不同时空尺度上的可信度能够影响到研究结果.作者就中国区域的月平均地表(2 m)气温和降水两种基本气候变量在空间分布及其变化趋势上对ERA-40和NCEP-2与观测资料之间的差异做了一些比较和分析,对两套再分析资料的可信度进行了初步的检验.结果表明:两套再分析资料基本上都能反映出中国区域的温度场和降水场的时空分布,尽管在中国西部,尤其是青藏高原地区的差异比较较大;再分析资料在东部地区的可信度高于西部,温度场的可信度要高于降水场,ERA-40可信度要高于NCEP-2.

      • ZHANG He, LIN Zhaohui, ZENG Qingcun

        2011,16(1):15-30, DOI: 10.3878/j.issn.1006-9585.2011.01.02

        Abstract:A study of the interaction and mutual response between dynamical core and physical parameterizations by atmospheric general circulation models CAM3.1 and IAP AGCM4.0 is presented. Both the two models were integrated 60 d with ideal physics (Held-Suarez forcing) and with full physical package, respectively. The results show that the mutual responses between dynamical core and physical parameterizations are very different in the troposphere at low latitudes and high latitudes. In the tropical troposphere, the variability of temperature tendency due to dynamical core and that due to physical parameterizations are both large and have significant contributions to the variability of total temperature tendency, and they are in inverse correlation to compensate each other. In the polar middle and upper troposphere, the variability of total temperature tendency mainly relies on the tendency due to dynamical core, while the variation of temperature tendency due to physics is very slow, which can be seen as a stationary forcing. Unlike the tropical regions, there is a positive correlation between the temperature tendency due to dynamics and that due to physics in Polar regions. Moreover, the interactions and mutual responses between the individual physical parameterizations are also analyzed. The results show that the variation of temperature tendency due to moist process is the largest of all the physical parameterizations, and it contributes most to the total temperature tendency due to physics. The variation of temperature tendency due to long wave radiation is also large at high latitudes, while the variation of temperature tendency due to short wave radiation and that due to vertical diffusion are relatively small. There is a negative feedback between the cooling rate of long wave radiation and the heating rate of short wave radiation.

      • YU Haiyan, LIU Shuhua, ZHAO Na, YU Yongtao, YU Liping, CAO Haiwei

        2011,16(3):389-398, DOI: 10.3878/j.issn.1006-9585.2011.03.14

        Abstract:Using the data of sunshine duration, temperature, wind speed, and precipitation from 194 basic/reference stations over China from 1951 to 2009, according to the climatic division, the whole domain of China is classified into 11 climatic regions. The authors studied the changes in annual and seasonal trends of the sunshine duration by using linear trend analysis and Morlet wavelet analysis, and analyzed the characteristics between the sunshine duration and the temperature, the wind speed, and the precipitation. It was found that the annual sunshine duration showed a significant decreasing tendency during the recent 59 years with a decreasing rate of 36.9 h·(10 a)-1. The trend variations of the annual sunshine duration in 11 climatic regions were similar with that in the whole nation, only had the difference in degree. The sunshine duration of China changed from intensive to weak in 1981. There is an obvious 7-10-year periodic oscillation for the annual sunshine duration of China before the mid 1990s. The sunshine duration of the four seasons had a bigger decreasing amplitude in the coastal areas than in the inland areas, and in the South than in the North. There was a negative correlation between the annual sunshine duration and the temperature (correlation coefficient is -0.52), but a positive correlation between the annual sunshine duration and the wind speed (correlation coefficient is 0.76), and a negative correlation between the annual sunshine duration and the precipitation (correlation coefficient is -0.27). The first two correlation coefficients and the last correlation coefficient passed 99.9% and 95% confidence levels,respectively.

      • Ren guoyu, Chen Yu, Zou Xuki, Zhou Yaqing, Wang Xiaoling, Jiang Ying, Ren Fumin, Zhang Qiang

        2010,15(4):354-364, DOI: 10.3878/j.issn.1006-9585.2010.04.02

        Abstract:综合极端气候指数对于极端气候变化监测、整体认识区域极端气候变化趋势及其原因和影响,具有实际意义。根据中国常年极端气候特点和不同种类极端气候事件的经济社会影响,选取全国平均高温日数、低温日数、强降水日数、沙尘天气日数、大风日数、干旱面积百分率和登陆热带气旋频数等7种极端气候指标,定义两个综合极端气候指数,分别为7种极端气候指标简单(等值权重)合成的综合指数I和加权(差异权重)合成的综合指数II。综合指数II主要依据各种极端气候事件引发的灾害严重程度及其社会影响大小,分别确定其对应指标的相对重要性和权重系数。分析结果表明:1956~2008年,综合指数I序列表现出明显的下降趋势,说明中国地区常见的极端气候事件总体有不断减少、减弱的趋势;同期综合指数II序列没有表现出明显的升降趋势变化,说明对中国地区具有重大经济和社会影响的极端气候事件频率总体上没有发生明显变化。就各个单项极端气候指数变化来看,全国平均年高温日数、强降水日数和干旱面积百分率呈上升趋势,但除高温日数外,其他指数趋势变化均不显著;全国平均年低温日数、沙尘天气日数和大风日数呈下降趋势,且趋势性均很显著;登陆中国大陆的热带气旋频数有所减少,但趋势不很明显。因此,在全球气候显著变暖的半个多世纪内,中国地区多数常见的极端气候事件发生频率,或者显著减少,或者变化不明显;而对全国经济和社会具有重大影响的主要极端气候事件,其频率总体上未见明显趋势变化。

      • Sun Guodong

        2009,14(4):341-351, DOI:

        Abstract:The LPJ DGVM (Lund Potsdam Jena Dynamic Global Vegetation Model), which is a process based model, is used to simulate the vegetation distribution and estimate the interannual variation of net primary production (NPP), heterotrophic respiration (Rh) and net ecosystem production (NEP)in China from 1981 to 1998. It is shown that there are six main plant functional types (PFTs) besides the desert,that is tropical broadleaved evergreen tree, temperate broadleaved evergreen tree, temperate broadleaved summergreen tree, boreal needleleaved evergreen tree, boreal needleleaved summergreen tree and C3 perennial grass. In China, the total NPP varies between 2.91 Gt·a-1(C) (1982) and 3.37 Gt·a-1(C) (1990), increases by 0.025 Gt (C) average per year and has an increasing trend of 0.96%. The total Rh varies between 2.59 Gt·a-1(C) (1986) and 319 Gt·a-1(C)(1998), grows by 1.05% per year and by 0.025 Gt(C) per year. The linear trend of NPP and Rh for C3 perennial grass is more remarkable than those for other PFTs. The simulation of NEP is reasonable when the fire is brought in the model. Annual total NEP varies between -0.06 Gt·a-1(C)(1998)and 0.34 Gt·a-1(C)(1992). It is demonstrated that the terrestrial ecosystem is carbon sink in China. The above results are similar to those simulated by other models.

      • ZHOU Liantong

        2009,14(1):9-20, DOI: 10.3878/j.issn.1006-9585.2009.01.02

        Abstract:利用1951~2000年我国西北干旱、半干旱区地温、气温和表面风场逐日4个时次(北京时间2、8、14和20时)的台站观测资料,以及NCEP/NCAR和ERA-40再分析资料,计算并比较了在我国西北地区春夏季感热输送的差异。分析结果表明:NCEP/NCAR和ERA-40的感热输送再分析资料都能显示出我国西北地区是欧亚大陆上的感热中心之一。从年代际时间尺度上,ERA-40再分析资料的感热资料更接近于实际台站观测资料计算得到的感热资料。

      • Li Chongyin, Zhu Jinhong, Sun Zhaobo

        2002,7(2):209-219, DOI: 10.3878/j.issn.1006-9585.2002.02.08

        Abstract:概括的介绍了中国科学家近几年在年代际气候变化方面的研究进展,包括中国气候的年代际变化特征,北大西洋涛动(NAO)和北太平洋涛动(NPO)与中国年代际气候变化的关系,北太平洋海面温度(SST)年代际模及其影响,大气环流系统的年代际变化以及气候突变问题.

      • REN Guo-Yu, CHU Zi-Ying, ZHOU Ya-Qing, XU Ming-Zhi, WANG Ying, TANG Guo-Li, ZHAI Pan-Mao, SHAO Xue-Mei, ZHANG Ai-Ying, CHEN Zheng-Hong, GUO Jun, LIU Hong-Bin, ZHOU Jiang-Xing, ZHAO Zong-Ci, ZHANG Li, BAI Hu-Zhi, LIU Xue-Feng, TANG Hong-Yu

        2005,10(4):701-716, DOI: 10.3878/j.issn.1006-9585.2005.04.01

        Abstract:总结了"十五"攻关课题有关中国温度变化研究的若干进展.在资料质量控制和序列非均一性检验及订正的基础上,更新了中国地面近50年、100年和1 000年气温序列.研究表明,不论是近54年还是近100年全国年平均地面气温升高趋势一般比原来分析结果表明的要强,分别达到0.25℃/10 a和0.08℃/10 a.中国现代增暖最明显的地区包括东北、华北、西北和青藏高原北部,最显著的季节在冬季和春季.近50多年中国近地面气候变暖主要是平均最低气温明显上升的结果,全国范围内极端最低气温也显著升高,而极端最高气温升高不多.中国与温度相关的极端气候事件强度和频率一般呈降低趋势或稳定态势.研究发现,城市化因素对中国地面平均气温记录具有显著影响,但在现有的全国和区域平均温度变化分析中一般没有考虑,因此需要在将来的研究中给予密切关注.在增温明显的华北地区,1961~2000年间城市化引起的年平均气温增加值达到0.44℃,占全部增温的38%,城市化引起的增温速率为0.11℃/10 a.中国其他地区的增温趋势中也或多或少反映出增强的城市热岛效应影响.20世纪60年代初以来中国对流层中下层温度变化趋势不明显,仅为0.05℃/10 a,比地面气温变化小一个量级;对流层上层和平流层底层年平均温度呈明显下降趋势,变化速率分别为-0.17℃/10 a和-0.22℃/10 a;整个对流层平均温度呈微弱下降趋势.中国对流层温度与地面气温变化趋势存在明显的差异,但这种差异在20世纪80年代初以后趋于减小.近千年来中国地面气温变化史上可能确存在"中世纪温暖期"和"小冰期"等特征性气候阶段,但"中世纪温暖期"的温暖程度似乎没有过去认为的那样明显.从全国范围看,11世纪末和13世纪中的温暖程度可能均超过了20世纪30~40年代暖期,表明20世纪的增暖可能并非史无前例.中国20世纪气候增暖的原因目前还不能给出明确回答.一些迹象表明,人类活动可能已经对中国的地面气温变化产生了影响,但太阳活动及气候系统内部的低频振动对现代气候变暖可能也具有重要影响.

      • TANG Xiao, WANG Zifa, ZHU Jiang, WU Qizhong, GBAGUIDI Alex

        2010,15(5):541-550, DOI: 10.3878/j.issn.1006-9585.2010.05.02

        Abstract:The Nested Air Quality Prediction Modeling System (NAQPMS) has been applied to the routine air quality forecast in Beijing during the Olympic Games. Monte Carlo method is used to analyze the uncertainty of ozone simulation of NAQPMS during the Olympic Games, from 8 to 24 Aug 2008. Latin hypercube sampling has been used for multi-variables sampling, and 50 ensemble runs have been made with 154 parameter uncertainties being considered together. By the temporal average, the most important parameter to the surface ozone output uncertainty in Beijing is the local precursor emissions during the day time. Other important factors include NO2 photolysis coefficient, wind direction, precursor emissions from the surrounding areas of Beijing, and vertical diffusion coefficient. The wind direction and precursor emissions from the surrounding areas of Beijing have the greatest impact on the uncertainty of daytime ozone simulation at higher levels (above about 150 m). The main uncertainty factors in ozone simulation at night are local NOx emissions and vertical diffusion coefficient. Given the predefined input uncertainties, the average uncertainty of ozone simulation is 19 ppb, ranging from 2 ppb to 49 ppb.

      • YANG Jin Hu, JIANG Zhi Hong, WANG Peng Xiang, CHEN Yan Shan

        2008,13(1):75-83, DOI: 10.3878/j.issn.1006-9585.2008.01.10

        Abstract:基于中国1955~2004年314个台站逐日降水资料,根据百分位值方法定义了不同台站的极端降水阈值,进而对中国年极端降水事件的时空特征进行了探讨分析。结果表明:江淮北部、湖南、四川西南部及西藏和新疆西部地区与中国其他区域呈反向变化特征,是中国年极端降水事件的主要空间异常模态;中国年极端降水事件的时间变化存在明显的区域性差异,东北、西北东部、华北表现为减少趋势,其中东北和华北发生了突变,而西北西部、长江中下游、华南及青藏高原表现为增加趋势,其中西北西部、长江中下游发生了突变;中国各分区年极端降水事件的周期振荡不完全一致;中国年极端降水事件与年降水量之间存在较好的相关性,从季节来看,夏季极端降水事件与年降水量的相关性最好。

      • Zou Xukai, Ren Guoyu, Zhang Qiang

        2010,15(4):371-378, DOI: 10.3878/j.issn.1006-9585.2010.04.04

        Abstract:基于中国606个地面台站1951~2008年的逐日降水量和气温资料,采用综合气象干旱指数CI统计分析了中国全国及十大江河流域近60年的干旱变化趋势。结果表明,近60年来,从整体来看,中国干旱面积呈现出弱的增加趋势。干旱持续时间长的几个中心分别位于北方的辽河流域西部、黄河流域东部、海河流域、西南诸河流域东南部等地,最长持续时间可达4个月以上;北方江河流域干旱面积一般表现出增加趋势,其中松花江流域、辽河流域、海河流域干旱面积出现显著的增加趋势,辽河流域、海河流域、黄河流域在20世纪90年代中后期至21世纪前期连续数年出现大范围干旱,南方大多数江河流域干旱面积的变化趋势不明显,只有西南诸河流域有显著的减少趋势。

      • YANG Hui, LI Chongyin, PAN Jing

        2011,16(1):1-14, DOI: 10.3878/j.issn.1006-9585.2011.01.01

        Abstract:Atmospheric processes associated with the South China Sea (SCS) monsoon trough which caused the heavy rainfall in pentad 3 of August 2007 in South China are analyzed using the reanalysis data of NCEP and satellite images. The results indicate that the Asian summer monsoon trough has independent space structure, convergence in the low layers and divergence in the high layers are in the south of the Asian summer monsoon trough. The climate analysis shows that both the Indian monsoon trough and the SCS monsoon trough reach their maximum in 〖JP2〗August. The SCS monsoon trough in pentad 3 of August 2007 was located in South China coastal areas and had strong intensity. The convergence in the low layers and divergence in the high layers were also stronger. The Indian monsoon trough was also stronger. The strengthened South Asian high locating over the Tibetan Plateau is the main cause for the strengthening of the Asian monsoon trough. The subtropical high in the western Pacific is located over Japan and is intensified, which is propitous to the northward 〖JP〗movement and the enhancing of the SCS monsoon and monsoon trough. The increased temperature over the Tibetan Plateau induces the stronger easterly in the upper levels, westerly in the low levels,and the enhancing convergence in the low layers and divergence in the high layers of the SCS monsoon trough. The long wave trough in the westerly belt is intensified and extends to Southwest China, which causes the SCS monsoon trough to become stronger. The SCS monsoon trough has an intraseasonal period. The intraseasonal oscillation has an important effect on the northward movement and enhancement of the SCS summer monsoon trough.


    主办单位:中国科学院大气物理研究所
    ParentUnit:中国科学院
    Editor in chief: 李崇银
    Associate editor:

    Editor Login


    Links
    Most Read More+
    Most CitedMore+
    Most Downloaded